build(deps): bump actions/checkout from 3 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...v4)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/ci.yaml

@@ -10,6 +10,6 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: build and test
         run: make docker_tests

.github/workflows/envoy-sync.yaml

@@ -29,15 +29,15 @@ jobs:
 
     # Checkout the repo
     - name: 'Checkout Repository'
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         ref: main
         fetch-depth: 0
         token: ${{ steps.appauth.outputs.token }}
 
     # Checkout the Envoy repo
     - name: 'Checkout Repository'
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         repository: envoyproxy/envoy
         ref: main

.github/workflows/golangci-lint.yaml

@@ -7,7 +7,7 @@ jobs:
     name: lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v3
         with: